We demonstrate electronic cooling of a suspended AuPd island using superconductor-insulator-normal metal tunnel junctions. This was achieved by developing a simple fabrication method for reliably releasing narrow submicron-sized metal beams. The process is based on reactive ion etching and uses a conducting substrate to avoid charge-up damage and is compatible with, e.g., conventional e-beam lithography, shadow-angle metal deposition, and oxide tunnel junctions. The devices function well and exhibit clear cooling, up to a factor of 2 at sub-Kelvin temperatures.
- electronic cooling
- superconducting junction devices
Muhonen, J. T., Niskanen, A., Meschke, M., Pashkin, Y. A., Tsai, J. S., Sainiemi, L., Franssila, S., & Pekola, J. P. (2009). Electronic cooling of a submicron-sized metallic beam. Applied Physics Letters, 94(7), . https://doi.org/10.1063/1.3080668